textproduct: Quad Cities

KEY MESSAGES

- Isolated to scattered severe risk has increased for this afternoon into early evening, with a Slight Risk (level 2 of 5) for northwest Illinois.

- We continue to have multiple days of severe weather risks this week. There is an Enhanced Risk for severe storms on Tuesday (level 3 of 5).

- Warm and seasonably humid conditions are expected through Wednesday this week.

UPDATE

Issued at 949 AM CDT Mon Apr 13 2026

Confidence has increased this morning for a risk of isolated to scattered severe storms this afternoon and early evening. Models are progging a compact mid-level shortwave to lift northeastward over the area this afternoon, along with a strengthening southwesterly 30-40 knot low-level jet, enhancing convergence. Temperatures well into the 70s and near 80 across our south, along with dew points into the mid to upper 60s, should support SBCAPE values between 1500-2500 J/kg this afternoon - ample instability to fuel convection. Additionally, progged mid-level lapse rates appear quite steep, with values around 7-8 C/km. All of this to say that the environment appears ripe for strong to severe storms. SPC has upgraded the severe risk to a Slight (level 2 of 5) for areas along and north of Galena, IL southeast towards Putnam county, IL, along with a Marginal Risk (level 1 of 5) now along and north of a line from Sigourney, IA to south- central Hancock county, IL.

Due to the steep mid-level lapse rates, large hail appears to be the primary threat, with damaging winds and a tornado being more of a secondary threat. However, if storms are able to become surface-based, this would help increase the damaging winds/tornado threat.

SHORT TERM /THROUGH TONIGHT/

Issued at 300 AM CDT Mon Apr 13 2026

Broad southwesterly flow aloft from the Desert Southwest into the Central U.S will continue through much of this week, resulting in active weather across the Midwest. A surface low will begin to organize across Nebraska today before tracking northeastward into NW Iowa and eventually central Wisconsin by tonight, placing eastern Iowa and northwest Illinois in the warm sector of this system. Forecast highs are in the upper 70s to lower 80s for most of the outlook area, with gusty southerly winds (20-30 mph) advecting a warm and increasingly humid air mass into the region (with Tds reaching the ~mid 60s). Elevated showers and thunderstorms are possible later this morning through the mid afternoon as increasing southwest winds aloft (850-700mb) lead to a period of lift/WAA and increase in MUCAPE to 1500-2000 J/kg per latest HREF. Gusty winds and hail would be the primary threats with the strongest cells.

The main area of convective initiation today will occur across Minnesota into west-central Wisconsin in the vicinity of a warm front. Forecast steering flow (850-300mb mean wind) and forward-prop. Corfidi vectors indicate these strong to severe clusters of storms will track mostly to the east or east- southeast through much of central and into southern Wisconsin this evening/tonight. What we'll have to watch for is if additional storms can fire back to the west near the surface low across NW Iowa. If this happens, then a line of storms could still drop in from the NW late at night, likely after 10 PM. Most models are not showing this scenario. However, the EC has been consistent on bringing at least scattered storms all the way down to central portions of the outlook area. SPC has pushed the Slight Risk for severe storms north of the area and has maintained a Marginal Risk down to the I-80 counties with the primary threats being isolated strong wind gusts and hail. PoPs haven't changed too much either as we are still messaging 20-50% along/north of Highway 34 for late tonight into early Tuesday AM.

LONG TERM /TUESDAY THROUGH SUNDAY/

Issued at 300 AM CDT Mon Apr 13 2026

Our attention for the long-term period starts right off the bat with another severe storm risk for Tuesday, and this one appears to be more likely to be active for us. The aforementioned warm front from Monday appears to be pulled southward by yet another surface low, this one developing over the central Plains (farther south than the Monday low pressure system). There remain some uncertainty on the influence of previous convection (if any develop) on how things evolve on Tuesday. If the boundary does reach our northwestern CWA by Tuesday afternoon/evening, it will be game on for strong/severe storms, especially considering the volatile thermodynamic and kinematic environment. As high temperatures warm into lower 80s for most, expect instability to be quite high, with the GEFS ensemble probability of SBCAPE of 2000 J/kg or higher around 50-80+ percent across our southeastern 2/3rds of the CWA. SPC has upgraded areas roughly north of Highway 34 to an Enhanced Risk (level 3 of 5), with all severe hazards possible, including large hail, damaging winds, and tornadoes.

For Wednesday through Friday, the active pattern will only continue as the primary upper-level longwave trough finally moves through the area Wednesday, followed by yet another one on Friday. We continue to be outlooked by SPC for Slight Risks both days in our region. Much uncertainty remains on the timing and severity as prior convection can augment the environment, but the various machine learning severe probability tools suggest these days to be volatile from an environmental perspective, so more to keep an eye on as we approach these portions of the week. Prepare for a busy severe weather week!

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 642 AM CDT Mon Apr 13 2026

Low stratus will remain over portions of eastern Iowa and northwest Illinois this morning with some early morning dense fog at CID. Prevailing IFR/LIFR ceilings are anticipated at DBQ and CID. Further south, periods of MVFR are expected at MLI and BRL, with brief IFR possible at MLI. By the afternoon, conditions should improve to MVFR/VFR and gusty southerly winds are expected once again, reaching around 25 kts. There is a chance for isolated showers and thunderstorms late this morning and this afternoon so have mentioned this potential in PROB30s.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.